Cultivating tool and apparatus incorporating same

ABSTRACT

A cultivating tool for breaking up and spreading plant material over and into the ground has opposed ends and upper, lower and intermediate portions extending longitudinally between said ends. The lower portion includes a cutting edge. The intermediate portion includes a forward outer surface extending concavely upwardly and forwardly from the lower portion to the upper portion and a rearward outer surface extending concavely upwardly and rearwardly from the lower portion to the upper portion. Cultivating apparatus includes the tool coupled to the end of a support arm. The arm may be an articulated arm and the coupling may be a pivotal coupling.

FIELD OF THE INVENTION

[0001] The present invention relates to cultivating tools and apparatus.More particularly, the present invention relates to tools and apparatusfor breaking up tree stumps and other plant material, driving broken upmaterial into the ground, and scraping and grading the ground.

BACKGROUND TO THE INVENTION

[0002] When forested land is harvested, tree stumps, branches and otherplant debris remain in or on the harvested ground. To recultivate thedebris must be either removed or worked around.

[0003] Often, stumps and other debris are fragmented and removed withequipment developed for other purposes, such as bulldozers, backhoes,excavators and the like. However, such equipment is primarily designedfor digging into or smoothing out a ground surface and, although able todo so, is not well adapted to efficiently crush, fracture or otherwisefragment large items such as stumps, branches and the like into smallerpieces and mix or turn them back into the ground where they arebiodegradable. If the remains of harvested trees are not effectivelyfragmented or are simply removed from the ground, decay of the wood andrecycling of minerals and other nutrients back into the soil can beimpaired or prevented.

[0004] Similarly, known equipment that is basically dedicated to thetask of breaking up tree stumps and other plant material is not welladapted to subsequently work debris into the ground or to prepare theground for cultivation by scraping or grading operations.

[0005] There is therefore a need for a single device specificallyadapted to fracture, pound, or otherwise fragment stumps and the like,and to also effectively separate the fragments so formed and turn theminto the ground and to perform these functions on a large scale.

SUMMARY OF THE INVENTION

[0006] In a broad aspect of the present invention there is provided acultivating tool comprising opposed ends and upper, lower andintermediate portions extending longitudinally between the ends. Thelower portion comprises a cutting edge extending between the ends. Theintermediate portion extends between the upper and lower portions, andcomprises firstly a forward outer surface extending between the ends andconcavely upwardly and forwardly from the lower portion to the upperportion and, secondly, a rearward outer surface extending between theends and concavely upwardly and rearwardly from the lower portion to theupper portion.

[0007] The cutting edge, complemented by the forward and rearwardconcave surfaces of the tool, is particularly suitable for splitting orfracturing plant material such as tree stumps and branches. As well thetool can be driven into and work the ground while mixing broken up plantmaterial into the ground in the process. Moreover, and again by reasonof its concave forward and rearward surfaces, the tool is particularlysuitable for bi-directional ground scraping and grading operations, andfor spreading concentrations of plant material over the ground.

[0008] In another aspect of the present invention, there is providedcultivating apparatus which includes a vehicle and an articulated arm incombination with a cultivating tool as described above. The articulatedarm comprises a boom pivotally mounted to the vehicle and extendingoutwardly therefrom for pivotal movement about a first axis; and a stickconnected to the boom. The stick extends from a proximal end pivotallyconnected to an outward end of the boom to a distal end of the stick,and is connected to the boom for pivotal movement about a second axisextending substantially parallel to the first axis. The tool is coupledto the distal end of the stick, and is preferably pivotally coupled forpivotal movement about a third axis extending substantially parallel tothe above mentioned first and second axes with the cutting edge of thetool extending substantially parallel to all three axes. Mostpreferably, the tool is pivotable to a position where it extends fromthe stick substantially in line with the stick. Such an arrangement notonly enables full advantage to be taken of the ground scraping andgrading characteristics of the tool but also enables the tool to be usedmost effectively for operations such as splitting a tree stump ordriving the tool into the ground.

[0009] The foregoing and other features and advantages of the presentinvention will now be described with reference to the drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0010]FIG. 1 is a perspective view of a cultivating tool in accordancewith the present invention.

[0011]FIG. 2 is a top view of the tool shown in FIG. 1.

[0012]FIG. 3 is a front elevation view of the tool shown in FIG. 1.

[0013]FIG. 4 is an end elevation view of the tool shown in FIG. 1

[0014]FIG. 5 is a partially exploded perspective view illustrating theassembly of a cultivating tool having the outward shape of the toolshown in FIG. 1.

[0015]FIG. 6 is a side elevation view of cultivating apparatus inaccordance with the present invention when being used to fracture a treestump. The apparatus includes the cultivating tool shown in FIG. 1.

[0016]FIG. 7 is a side elevation view of the cultivating apparatus shownin FIG. 6 when being used to scrape or grade a ground surface.

[0017]FIG. 8 is a perspective view, partially cut-away, showing in moredetail how the tool shown in FIG. 1 is coupled in the apparatus shown inFIGS. 6-7.

DETAILED DESCRIPTION OF INVENTION

[0018] Referring now to FIGS. 1-4 with initial attention on FIGS. 3-4,there is shown a tapered or wedge-shaped cultivating tool generallydesignated 2 which comprises a lower portion 8, an intermediate portion10, and an upper portion 12, all of which portions extend longitudinallybetween opposed, flat ends or end surfaces 14, 14′ of the tool. Lowerportion 8 includes a cutting edge 16 extending longitudinally betweenends 14, 14′, a generally flat forward surface 17 extending upwardly andforwardly from edge 16 to intermediate portion 10, and a generally flatrearward surface 18 extending upwardly and rearwardly from edge 16 tointermediate portion 10. Intermediate portion 10 extends between upperand lower portions 8, 12 and includes both a forward outer surface 5which extends between ends 14, 14′ and concavely upwardly and forwardlyfrom lower portion 8 to upper portion 12, and a rearward outer surface 6which likewise extends between ends 14, 14′ and concavely upwardly andrearwardly from lower portion 8 to upper portion 12. Upper portion 12includes a trailing end 7.

[0019] Tool 2 also includes a pair of spaced mounting brackets 20, 20′which preferably are welded to the positions shown. Each bracketincludes a pair of pin bosses 22, 23. Boss 22 of bracket 20 is axiallyaligned along axis a3 with boss 22 of bracket 20′. Likewise, boss 23 ofbracket 20 is axially aligned along axis a4 with boss 23 of bracket 20′.By means of brackets 20, 20′, tool 2 is releasably and pivotallycouplable to a support arm such as the stick portion of a mechanical armin the manner described below. Apart from brackets 20, 20′, tool 2 issubstantially symmetric on either side of an imaginary vertical planecontaining cutting edge 16.

[0020] In a currently preferred embodiment, tool 2 is fabricated fromsteel and has an overall length (between ends 14, 14′) and height ofabout 6 by 5 feet. The maximum thickness of the tool between outersurfaces 5, 6 is about 2½ feet. Trailing end 7 is given a convex shapeto facilitate mounting of the tool to the stick of a conventionalexcavating machine as described below, including the use of commerciallyavailable mounting brackets 20, 20′ normally used to mount aconventional excavating bucket (not shown) to the stick.

[0021] A cultivating tool having the outward shape of the tool shown inFIG. 2 may be readily assembled from part segments. One possiblebreakdown of parts and their manner of assembly is illustrated in FIG.5. The parts are fabricated from steel.

[0022] In FIG. 5, there is shown in addition to mounting brackets 20,20′ a shaped, hollow module 180 which includes a longitudinallyextending centrally positioned groove 182 in its lower surface, a pairof opposed end plates 190, 190′ which each include a groove 192 thataligns with groove 182, and a rail section 210 which includes alongitudinally extending tongue 212 centrally positioned on its uppersurface. The shape of end plates 190, 190′, matches the cross section ofmodule 180. The hollowing of module 180 serves to substantially reduceoverall weight while still providing a rugged implement.

[0023] The length of rail section 210, including tongue 212, correspondsto the length of module 180 plus the combined wall thicknesses of endplates 190, 190′. Tongue 212 is sized to slidingly fit within grooves182 and 192. While the use of the tongue and groove arrangement iscertainly not considered to be essential, it is considered to provideadded strength and it does assist to align the various parts duringassembly.

[0024] When the exploded parts shown in FIG. 5 are brought together, theoverall structure generally becomes that of tool 2 shown in FIG. 1. Moreparticularly, rail section 210 embodies lower portion 8 of tool 2 asshown in FIGS. 3-4. The lowermost part of rail section 210 correspondsto cutting edge 16. Further, the convex upper surfaces of module 180together with the corresponding upper surfaces of end plates 190, 190′will define trailing end 7 as shown in FIG. 1. As well, the concaveforward and rearward outer surfaces of module 180 together with thecorresponding concave forward and rearward outer surfaces of end plates190, 190′ will define forward and rearward outer surfaces 5, 6 as shownin FIG. 1. Overall, module 180 together with end plates 190, 190′ thuswill be seen to substantially define intermediate and upper portions 10,12 of tool 2 as shown in FIG. 1.

[0025] The various exploded parts shown in FIG. 5 are assembled bywelding. At least in the case of rail section 210, it is preferablyattached with a welding composition having a melting point lower thanthat of the parts being welding. Then, if rail section 210 becomesdegraded by wear and tear or other damage, it can readily be replacedwith a new rail section. As such, it can be considered as beingreleasably attachable to the intermediate portion of the overall tool.

[0026] It will be appreciated by those skilled in the art that the partsegments shown in FIG. 5 are merely exemplary and that a cultivatingtool similar to that shown in FIG. 1 could be assembled from differentlyconfigured parts. Further, it will be appreciated that the parts thatare utilized may be adjoined by various means other than welding—forexample: bolts, screws, rivets and/or the like.

[0027] Referring now to FIGS. 6-8 there is shown cultivating apparatuswhich includes a vehicle (viz. a conventional excavator tractor)generally designated 300, a boom 310 pivotally mounted to the vehicle ata position hidden from view and extending outwardly therefrom forpivotal movement about an axis approximately at point a1, and a stick330 extending from a proximal end pivotally connected by pivot pin 340to an outward end of boom 310 for pivotal movement about the axis of pin340. Stick 330 extends from the proximal end to a distal end wherecultivating tool 2 is pivotally connected by pivot pins 350, 352 andconventional pivot links 360, 362 for pivotal movement about the axis ofpin 350. It will be noted that the axis of pin 340, the axis of pin 350and the axis through point a1 all run in parallel. As well, the cuttingedge of tool 2 extends substantially parallel to these axes.

[0028] Although there are a range of possibilities, it should be notedthat the particular manner in which tool 2 is coupled to vehicle 300 iswidely used for the mounting of excavator buckets to vehicles such asvehicle 300 and to other vehicles such as back hoes and the like.

[0029] In the embodiment illustrated in FIGS. 6-8, the angular or pivotposition of cultivating tool 2 relative to stick 330 is controlled andvaried in a conventional manner by linear movement of cylinder rod 370driven by hydraulic cylinder or actuator 371. Further, the angular orpivot position of stick 330 relative to boom 310 is controlled andvaried in a conventional manner by linear movement of cylinder rod 375driven by hydraulic cylinder or actuator 376. Finally, the angular orpivot position of boom 310 relative to vehicle 300 is controlled andvaried in a conventional manner by linear movement of cylinder rod 380driven by hydraulic cylinder or actuator 381. Such controls enable theposition and movement of tool 2 to be fully controlled for variouspurposes.

[0030] The use of tool 2 to split or fracture material (in this case atree stump 500) is illustrated in FIG. 6. To achieve optimum effect, thetool is pivoted to a generally vertical position extending substantiallyin line with stick 330 which is also pivoted to a generally verticalposition. In this position, the tool can be pounded on stump 500 notonly with its own weight and momentum but also with that of stick 330,and with forces transmitted to stick 330 and the tool from boom 310.

[0031] The use of tool 2 to spread material such as broken up plantdebris is illustrated in FIG. 7. Here, cutting edge 16 of the tool ispositioned on or proximate to ground surface 600 and the tool is movedbackward from the solid line position shown in FIG. 7 or forward fromthe broken line position shown in FIG. 7. During such movements, somedebris can slip under the cutting edge while other debris, depending onthe direction of movement, travels up and cascades down from therearward or forward concave outer surface of the tool. For suchoperations, users in most cases are apt to find that better results canbe achieved if tool 2 is pivoted to an angle between about 30 and 60degrees from the plane of the ground surface rather than to a verticalposition as shown in FIG. 6.

[0032] It will be apparent to those skilled in the art that acultivating tool in accordance with the present invention need not beconstructed in a modular fashion though this is presently considered tobe the most convenient construction method. A solid, heavier tool couldalso be used, and a range of breakdown structures other than thatdepicted in FIG. 5 are possible. Further, the design of the mountingassembly, the form and attachment of mounting brackets, the movement andarticulation of the tool on a support arm can be varied in numerousways. Many such variations within the scope of the following claims arepossible and will occur to those skilled in the art.

I claim:
 1. A cultivating tool comprising opposed ends and upper, lowerand intermediate portions extending longitudinally between said ends,(a) said lower portion comprising a cutting edge extending between saidends; (b) said intermediate portion extending between said upper andlower portions, said intermediate portion comprising: (i) a forwardouter surface extending between said ends and concavely upwardly andforwardly from said lower portion to said upper portion; and, (ii) arearward outer surface extending between said ends and concavelyupwardly and rearwardly from said lower portion to said upper portion.2. A cultivating tool as described in claim 1, further including meansfor coupling said tool to a support arm.
 3. A cultivating tool asdefined in claim 2, wherein said lower portion of said tool isreleasably attachable to said intermediate portion of said tool.
 4. Acultivating tool as defined in claim 1, wherein said lower portion ofsaid tool is releasably attachable to said intermediate portion of saidtool.
 5. Cultivating apparatus comprising: (a) a support arm; and, (b) acultivating tool releasably couplable to said support arm, said toolcomprising opposed ends and upper, lower and intermediate portionsextending longitudinally between said ends, said lower portioncomprising a cutting edge extending between said ends, said intermediateportion extending between said upper and lower portions, saidintermediate portion comprising: (i) a forward outer surface extendingbetween said ends and concavely upwardly and forwardly from said lowerportion to said portion; and, (ii) a rearward outer surface extendingbetween said ends and concavely upwardly and rearwardly from said lowerportion to said upper portion.
 6. Cultivating apparatus as defined inclaim 5, wherein said lower portion of said tool is releasablyattachable to said intermediate portion of said tool.
 7. Cultivatingapparatus comprising: (a) a vehicle; (b) a boom pivotally mounted tosaid vehicle and extending outwardly therefrom for pivotal movementabout a first axis; (c) a stick extending (i) from a proximal endpivotally connected to an outward end of said boom for pivotal movementabout a second axis extending substantially parallel to said first axis(ii) to a distal end of said stick; (d) a cultivating tool coupled tosaid distal end of said stick, said tool comprising opposed ends andupper, lower and intermediate portions extending longitudinally betweensaid ends, said lower portion comprising a cutting edge extendingbetween said ends, said intermediate portion extending between saidupper and lower portions, said intermediate portion comprising: (i) aforward outer surface extending between said ends and concavely upwardlyand forwardly from said lower portion to said upper portion; and, (ii) arearward outer surface extending between said ends and concavelyupwardly and rearwardly from said lower portion to said upper portion.8. Cultivating apparatus as defined in claim 7, wherein said lowerportion of said tool is releasably attachable to said intermediateportion of said tool.
 9. Cultivating apparatus as defined in claim 7,wherein said tool extends from said stick substantially in line withsaid stick.
 10. Cultivating apparatus as defined in claim 9, whereinsaid lower portion of said tool is releasably attachable to saidintermediate portion of said tool.
 11. Cultivating apparatus as definedin claim 7, wherein said tool is pivotally coupled to said distal end ofsaid stick for pivotal movement about a third axis extendingsubstantially parallel to said first and second axes, said cutting edgeextending substantially parallel to said first, second and third axes.12. Cultivating apparatus as defined in claim 11, wherein said lowerportion of said tool is releasably attachable to said intermediateportion of said tool.
 13. Cultivating apparatus as defined in claim 12,wherein said tool is pivotal about said third axis to a position wheresaid tool extends from said stick substantially in line with said stick.14. Cultivating apparatus as defined in claim 13, wherein said lowerportion of said tool is releasably attachable to said intermediateportion of said tool.